Trench falsework panel

ABSTRACT

The invention concerns a panel for use in trench falsework as part of a box construction or in sliding forms in civil-engineering. The falsework is easy to mount in place and is resistant to buckling, even along the triangular hollow section which forms the cutting edge at the bottom of the panel, by virtue of the fact that the triangular hollow section incorporates single-piece steel suspension rings which have a partly rounded and partly straight outside circumference. The outside shape of the rings fits into the surface of the metal sheet surrounding the ring, the straight part of the rings forming part of the cutting edge and the rounded part of the rings being welded to the adjacent parts of the hollow section.

BACKGROUND OF THE INVENTION

The invention relates to a lining plate, consisting of profiled sheetmetal elements enclosed between two rectangular sheet metal covers andcircumferential hollow profiles welded to the sheet metal covers, to beused in connection with trench lining in below-grade construction.

A lining plate with a circumferential hollow profile is described in DE30 15 110 A1. This lining plate, also provided for shoring up trenchwalls, has exterior sheet metal plates essentially extending over theentire plate surface, a rectangular frame supporting the edges of theexterior sheet metal plates, and profiles which reinforce the frame andintersect each other. Together with the exterior sheet metal plates, theframe profiles constitute closed hollow box profiles, i.e. a plate framedelimiting the plate body. In detail, the latter can consist of an upperanvil cross piece (pressure cross beam), on which pressure or blows aredirected during operation; of lateral closing profiles (vertical crossbeams) which can have a rectangular cross section, the same as the anvilprofiles; and of a lower pointed or cutting profile of triangular crosssection.

In the course of assembling a lining box of two lining plates, generallythe one lining plate is placed on the ground, then braces (these arespacers between lining plates standing opposite each other in thetrench) are fastened in the plate resting on the ground; the secondplate is then lifted over the first plate by a crane and the braces areinserted from below into the second plate and fastened there. Duringthis operation it is necessary for the second plate to be accuratelydirected by the crane and securely held, so that no accidents can occur.The assembly is furthermore made considerably easier if the plates arehung horizontally, since there will be no jamming when the spindle isinserted. To this end, in actual operations the exterior narrow sides ofthe two lateral closing profiles of the plate are pulled forward as"free" triangular sheet metal brackets up to approximately the tip ofthe cutting edge of the lower profile and are equipped with a suspensionhole. During horizontal directing the crane can act on the twotriangular brackets and further attachment points associated with theupper plate edge, i.e. at four points.

The drilled brackets provided laterally at the longitudinal ends of thecutting edge are generally bent after a short period of use, or evenbroken off. In actual use the lining plate is therefore held at thecutting edge during assembly in that the crane hooks are simply placedover the cutting edge--without a particular attachment point. Then thereis always the danger that one or the other hook slides to the side whenthe plate is lifted, so that the entire plate begins to tilt.

SUMMARY OF THE INVENTION

It is the object of the invention to provide a fastening possibility asthe attachment means for a crane hook, a cable or the like at thepointed or lower edge or cutting edge of the lining plate, in particularfor suspending the lining plate in a horizontal position, by means ofwhich neither the driving of the lining plate into the ground ishampered nor the cutting edge of the lining plate, embodied as a hollowprofile, is weakened against torsional buckling or the like, and whichcannot be damaged, even by driving the lining plate into the ground orpulling the lining plate further along the trench. In addition, thenovel fastening or attachment means is intended to permit the directengagement of a crane hook, similar to the conventional triangularbrackets provided on the longitudinal ends of the cutting edge.

The attainment of the object in accordance with the invention lies inthat the pointed hollow profile constituting the cutting edge of thelower plate edge contains at least one massive suspension ring made ofsteel of a cross section which is at least approximately congruent withthe triangular cross section of the cutting edge and with a partiallystraight and otherwise approximately semicircular exteriorcircumference, whose rounded area is welded all around to the pointedhollow profile, and whose straight area forms a part of the lower plateedge.

Thus, in accordance with the invention a massive ring--preferablyconsisting of cast steel or forged steel--is inserted into the tip orcutting edge of the lining plate which is embodied as a hollow profile,whose exterior contour on the one hand exactly fits the surface of thecover surfaces surrounding the ring and, on the other hand, constitutesa part of the cutting edge as well as its edge itself.

The suspension ring in accordance with the invention is situated insidethe hollow profile frame reinforcing the lining plate, but the ring doesnot weaken the frame, since because of its massive design its inherentstiffness is at least as great as the stiffness of the sheet steel whichmust be cut out of the hollow profile for inserting the ring, and sinceit becomes a part of the hollow profile because of the all aroundwelding with the remaining hollow profile elements.

An essential advantage of the suspension ring in accordance with theinvention lies in that the ring opening can lie close enough to thecutting edge that a crane hook--if necessary with a hook safetydevice--can grip over the bar remaining between the cutting edge and theopening. Maximum safety is provided for possible assembly work by meansof this, for example in connection with a lining box. An advantage ofthe attainment of the object in accordance with the invention connectedwith this lies in that the suspension ring installed in the cutting edgecan resist the forces acting in the course of driving it into the groundat least as well as the remaining parts of the cutting edge, and thatwhen pulling the lining plate along in the longitudinal direction of thetrench, the suspension ring is neither subjected to an additional loadnor does it hamper the forward pulling of the plate, so that it actslike a part of the remaining cutting edge during operation.

Details of the invention will be explained by means of the schematicrepresentation of an exemplary embodiment shown in the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of the inside (side facing inside the trench) of alining plate;

FIG. 2 is a sectional view of a lining box of two lining plates in FIG.1, approximately along the section II--II in FIG. 1;

FIG. 3 is an enlarged representation of the section through a shoesupport housing with support shoe in FIG. 2; and

FIG. 4 is a section along the line IV--IV in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In the accompanying drawings and in the following description thereof,the reference numerals in the drawings identify components of thepresent invention as indicated below:

    ______________________________________                                                    List of Reference Numerals                                        ______________________________________                                         1            Lining plate                                                     2            Inner sheet metal cover                                          3            Outer sheet metal cover                                          4            Profiled sheet metal element                                     5            Rectangular frame construction                                   6            Frame corner                                                     7            Upper hollow profile                                             8            Lateral hollow profile                                           9            Pointed hollow profile                                           9a           Longitudinal ends                                               10            Upper plate edge                                                11            Lateral plate edge                                              12            Cutting edge                                                    13            Lower plate edge                                                14,15         Cathetus                                                        16            Hypotenuse                                                      17            Receptacle housing                                              18            Suspension ring                                                 19            Opening (18)                                                    20            Rounded area (18)                                               21            Straight area (18)                                              22,23         Axial surfaces (18)                                             24            Bar (18)                                                        25            Suspension eye                                                  26            Attachment means                                                27            Hoisting ring                                                   28            Eye (27)                                                        ______________________________________                                    

The lining plate represented in FIGS. 1 and 2, identified as a whole by1, consists of two rectangular sheet metal covers 2 and 3 with profiledsheet metal elements 4 enclosed between them and a circumferentialhollow profile frame 5 welded to the cover surfaces 2 and 3, which as awhole is identified as the rectangular frame structure 5 and consists ofrespectively one hollow profile 7, 8 or 9 uninterruptedly extending fromframe corner 6 to frame corner 6. The ends of the hollow profiles 7 to 9meeting at the frame comers 6 are welded together in such a way that therectangular frame construction 5 acts as one piece. The hollow profiles7 to 9 can be longitudinally welded or seamlessly welded or drawn.Preferably these are not only U- or C-profiles, but hollow profilesclosed in a tube-like manner. In detail the frame structure 5 inaccordance with FIG. 1 consists of a pressure cross beam 7 particularlystabilized against flexural bucking at the upper plate edge 10, ofrespectively one vertical cross beam 8 especially stabilized againstforces in the vertical longitudinal direction at the plate sides 11, anda pointed hollow profile 9 having a cutting edge 12 on the lower plateedge 13, whose longitudinal ends 9a are suitably embodied especiallyadvantageously, particularly massively, where they adjoin the lower edge13. While the pressure cross beam 7 and the vertical cross beam 8 areintended to have a rectangular cross section, the pointed hollow profileof the lower edge 13 has an cross section approximately in the form of aright triangle, whose one cathetus 14 lies vertically in respect to theplane of the rear wall 2, 3, whose other cathetus 15 lies in the planeof the exterior cover surface 3 which, during lining, faces the soil,and whose hypotenuse 16 is intended to face the interior of the trench.If required, receptacle housings 17 provided for placing and fasteningbraces (not shown) in place are inserted with the opening at the sheetmetal cover 2, which is on the inside during lining, into the liningplate 1 adjoining or adjacent to the hollow profiles 8.

In accordance with the invention at least one suspension ring 18 isintegrated with a suspension opening 19 into the cutting edge 12adjoining the lower edge 13 of the pointed hollow profile 9. Thesuspension ring 18 has a rounded circumferential area 20 and a straightcircumferential area 21 situated parallel with a tangent of the opening19. Details are shown in enlargement in FIGS. 3 and 4. It is importantamong other things that the suspension ring 18 has a cross section whichis congruent with the triangular cross section of the cutting edge 12.FIG. 4 shows the cross section of the pointed hollow profile 9 andtherefore also the cross section of the cutting edge 12 and thesuspension ring 18 integrated therein by welding, that the axialsurfaces 22 and 23 of the suspension ring 18, which are placed obliquelyin relation to each other, the same as the cutting edge surfaces 15, 16,are fitted as exactly a possible into the two surfaces, defined by thecathetus 15 and the hypotenuse 16, of the pointed hollow profile 9.

The suspension ring 18 has a bar 24 essentially extending parallel withthe lower plate edge 13 between the straight circumferential area 21 andthe opening 19. It preferably is designed in such a way that it issimultaneously sufficiently strong or voluminous to be as stable againstbuckling or breaking as the remaining part of the lower cutting edge 12,and yet slim enough to assure the direct suspension and the overlappingsecuring of a crane hook or like hoisting means. A hook safety isenvisioned in connection with overlapping securing which in the courseof suspending the hook is placed around the bar as a continuation of thehook point, as it were.

If the lining plate 1 is to be directed approximately horizontallyduring assembly, the crane can take hold, for example with a cable orhook, directly in the opening 19 of the suspension ring 18. With itssafety the hook can reach around the lower bar 24 adjoining the lowerplate edge 13, since the opening 19 is intended to lie correspondinglyclose to the cutting edge 12. If it is intended to lift the platehorizontally with the aid of the two suspension rings 18 in FIG. 1, thelifting means also need to act on at least one other place of the liningplate 1. To this end, in accordance with the exemplary embodiment,suspension eyes 25 with built-in attachment means 26 (for crane hoistingmeans or the like) are provided approximately in the upper third of thesurface of the lining plate, but at a distance away from the adjoininghollow profiles 7 and 8. In place of this it is also possible forhoisting rings 27 to be welded with the aid of eyes 28 to an upper partof the frame 5, in particular on the hollow profile 7. The hoistingmeans of the crane can, among other things, also act on correspondinglydesigned attachment points of the receptacle housing 17.

A lining plate intended for employment in connection with trench liningin below-ground construction as a component of a lining box, or withsliding rail lining, becomes assembly-friendly and remains secureagainst buckling even at its triangular hollow profile with the cuttingedge, if massive suspension rings made of steel with partially straightand partially rounded exterior circumferences are inserted into thetriangular hollow profile, whose axial exterior contour fits into thesurface of the sheet metal cover surrounding the ring, whose straightcircumferential part forms a part of the edge of the cutting edge andwhose rounded circumferential part is welded together with the adjoiningparts of the hollow profile.

What is claimed is:
 1. A lining plate for use as a trench lining inbelow grade construction, the lining plate comprising profiled sheetmetal elements enclosed between two rectangular sheet metal covers andperipheral hollow profiles welded to the sheet metal covers, wherein oneof the hollow profiles comprises a lower cutting edge having atriangular cross-section defining a pointed lower plate edge and atleast one massive metal suspension ring having a cross section which isat least approximately congruent with the triangular cross section ofthe lower cutting edge and having an exterior shape with a partiallystraight portion forming a part of the lower plate edge and anapproximately semicircular portion welded thereabout to the one hollowprofile.
 2. The lining plate in accordance with claim 1, wherein thesuspension ring defines an opening therethrough and comprises a barbetween the opening and the lower plate edge, the bar being at least asresistant to buckling as the remainder of the lower cutting edge andpermitting the direct suspension and securing of a hoisting means. 3.The lining plate in accordance with claim 1 or 2, wherein the suspensionring is made of steel.
 4. A lining plate for use as a trench lining inbelow grade construction, the lining plate comprising a plate bodyhaving a lower cutting edge of a triangular cross section defining apointed lower plate edge and at least one massive suspension ring of across section which is at least approximately congruent with thetriangular cross section of the lower cutting edge and having anexterior shape with a partially straight portion forming a part of thelower plate edge and an approximately semicircular portion weldedthereabout to the lower cutting edge.
 5. The lining plate in accordancewith claim 4, wherein the suspension ring defines an openingtherethrough and comprises a bar between the opening and the lower plateedge, the bar being at least as resistant to buckling as the remainderof the lower cutting edge and permitting the direct suspension andsecuring of a hoisting means.
 6. The lining plate in accordance withclaim 4 or 5, wherein the suspension ring is made of steel.